1. Field of the Invention
The present invention relates to a monoclonal antibody that specifically binds to vascular cell adhesion molecule-1 (hereinafter, referred to simply as “VCAM-1”). Specifically, the present invention relates to a monoclonal antibody that specifically binds to both human and mouse vascular cell adhesion molecule-1 (VCAM-1), a method for producing the same, a composition for diagnosis or treatment comprising them and a method for diagnosis or treatment using them. The invention also relates to a method of inhibiting VCAM-1 mediated leukocyte adhesion to endothelial cells.
2. General Background and State of the Art
Cell adhesion molecules (CAMs) are important for the recruitment of leukocytes from circulating blood to the endothelium in the inflammatory reaction. Endothelial cells as an active responder in response to extracellular stimuli express various CAMs, such as E- and P-selectins and members of the immunoglobulin superfamily including intercellular cell adhesion molecule (ICAM)-1, -2, and -3, vascular cell adhesion molecule (VCAM)-1, which interact with carbohydrate ligands and integrins expressed in leukocytes. Accordingly, because of the central roles of CAMs that mediate the accumulation of leukocytes in inflammation, blocking CAMs is thought to be a promising strategy for therapeutic intervention in inflammatory disorders.
Among CAMs, VCAM-1, CD106, is expressed in dominantly and inducibly expressed on endothelial cells upon activation by lipopolysaccharide (LPS), interleukin-1 (IL-1), interferon-γ (INFγ) or tumor necrosis factor alpha (TNFα). VCAM-1 binds to very late antigen-4 (VLA-4), α4β1 integrin, expressed on activated leukocytes in inflammation and immune rejection and plays a critical role in promoting the interaction between endothelial cells and leukocytes including monocyte and T cells. Currently, increasing attention is being paid to VCAM-1-VLA-4 interaction as targets for therapeutic interventions in inflammatory diseases. For example, small peptide antagonists of integrin α4β1, TR14035, and a α4 integrin antibody, Tysabri or Natalizumab, are effective in ameliorating pathology in inflammatory bowl disease, multiple sclerosis, and asthma. TR14035 and Natalizumab are currently in Phase II and III respectively. Additionally, according to recent increasing evidence, VCAM-1 is also closely implicated in cancer progression. In detail, first, soluble VCAM-1 is regarded as a marker of the diagnosis of various cancers. Second, VCAM-1 which is expressed in tumor periphery plays a key role in facilitating the homing of bone marrow-derived progenitor cells for tumor neovascularization. Third, VCAM-1 is important in extravasation of circulating cancer cells, a key step in metastasis. Fourth, down-regulation of VCAM-1 in a highly immune-resistant cancer cell line was found to lead to reduced tumor immune evasion. In this regards, there are increasing needs for diagnosis and therapy of anti-adhesion drugs in cancer treatment.
Despite recent attention to VCAM-1-VLA-4 interaction, the development of a neutralizing antibody to VCAM-1 has not been actively studied. Although M/K-2.7, a monoclonal antibody to mouse VCAM-1, is recently developed and shows reduced effect on joint inflammation in collagen-induced arthritis mouse model, the usefulness of the antibody should be further tested for clinical application. Until now, most clinical trials of anti-adhesion therapies have used humanized monoclonal antibodies. In this regards, the development of a monoclonal antibody specific to mouse and human VCAM-1 for preclinical and clinical study and capable of the conversion of humanized antibody is being urgently required.
In the present study, we for the first time generated a rabbit/human chimeric monoclonal antibody specific to human and mouse VCAM-1 which contains rabbit heavy chain (VH) and light chain (VL) variable domain and human heavy chain (CH1) and light chain (CL) constant domain from synthetic antibody library. This antibody specifically recognizes human, mouse, rat, and porcine VCAM-1 expressed in various cell types such endothelial cells and skeletal muscle cells. Furthermore, it has a strong activity of blocking the interaction between U937 human promonocytic leukocytes and activated endothelial cells. Finally, we identified the epitope regions against VCAM-1 specific antibody whose sequences are derived from mouse VCAM-1. In summary, the present application describes a potential therapeutic monoclonal antibody dual specific to human and mouse VCAM-1.